Brother HL-5130 Service Manual page 249

<How to Read the Drum Unit Life>
The drum unit life is shown by the bar at the center of Print Settings;
• It initially indicates 100% and gradually decreases.
• It indicates 0% when the Drum LED is blinking.
• It stays at 0% even if further printing is done.
<The difference of the drum unit life and the drum counter>
The drum unit life is based on the page counter. If the average number of drum rotations is
more than the number of drum rotations in non-continuous printing, however, the drum unit life
is counted by the number of drum rotations.
Since the drum counter printed in Print Settings is an actual page counter after a new drum
unit is replaced, the drum unit life may be different from the drum counter.
For details on the difference between the drum unit life and drum counter, refer to the drum
unit life calculation below;
<How to calculate drum unit life>
**Printing time for 1 page/job in discontinuous printing = 10 seconds
(Page counter reduced by the number of drum rotations) =
(Time of motor rotation) ÷ 0.89 ÷ 8.4
Example:
1 page/job (5 + 8.4) / 8.4 = 1.60
2 pages/job (5 + 8.4 + 3.3) / 8.4 = 1.99
18 pages/job (5 + 8.4 + 3.3 x 17) / 8.4 = 8.27
If printing 1 page per job with cold start, the drum unit life is decreased earlier.
(2) Counter information, history information
The counter and history information related to the following term is included. When it reaches
the maximum count, each term is no longer counted.
• Device status
The total number of pages printed. The maximum count is 1 million pages.
• Average Coverage (Letter)
• Total pages printed (TRAY)
For Tray2 and Duplex, it is indicated only when they are equipped. The maximum count for
each item is 1 million times.
• Total pages printed (PAPER)
The number of A4/Letter, A4Long/Legal/Folio, B5/Excutine, Envelope, and other paper types
used. The maximum count for each item is 1 million times.
The number of pages calculated from drum rotations
Cold start (page)
7-7
HL-5130/5140/5150D/5170DN SERVICE MANUAL
Hot start (page)
8.4 / 8.4 = 1
(8.4 + 3.3) / 8.4 = 1.39
(8.4 + 3.3 x 17) / 8.4 = 7.68